The aim of this study is to evaluate the effects of diesel from direct coal liquefaction (DDCL) and diesel from indirect coal liquefaction (DICL) on combustion and emissions. A six-cylinder turbocharged diesel engine fueled with DDCL, DICL, petroleum diesel (PD), 58% DDCL, and 42% DICL blended by volume (BD58) is used. The experiments are carried out at 1400 and 2300rpm engine speeds and various engine loads (10%, 25%, 50%, 75%, and 90% of the full-load). The results show that the brake thermal efficiency (BTE) of PD was higher than that of CTL (the maximum difference was 2%) at medium and high loads. At 10% load of 1400 rpm, the CO, HC and formaldehyde emissions of DDCL are 88.9%, 44.3% and 26.5% higher than those of PD respectively, and the CO, HC, and formaldehyde emissions of DICL are 30.1%, 15.3%, and 15.2% lower than those of PD. The differences among four fuels decrease rapidly with the increase of load. The NO_X emissions of PD are the highest due to high nitrogen content (102.3 μg/g) and low hydrogen-carbon (H/C) ratio. The fuel with higher cetane number has less formaldehyde emission at low loads, while the fuel with lower H/C has less formaldehyde emission at high loads. The particle size distribution shows a bimodal shape at different loads and the peak particle size of accumulation mode and nucleation mode all increases with the increase of load. The particulate emission of different fuels from high to low is the order of PD > DDCL > BD58 > DICL. In addition, the emissions of polycyclic aromatic hydrocarbons (PAHs) and toxicity equivalent (TE) of PD are highest at all loads. The proportion of soluble organic fractions (SOF) from DDCL, DICL, and BD58 is higher than that of PD.

本研究的目的是评估直接煤液化 (DDCL) 柴油和间接煤液化 (DICL) 柴油对燃烧和排放的影响。使用以 DDCL、DICL、石油柴油 (PD)、58% DDCL 和 42% DICL 按体积混合 (BD58) 为燃料的六缸涡轮增压柴油发动机。实验在 1400 和 2300rpm 发动机转速和各种发动机负载（10%、25%、50%、75% 和 90% 的满载）下进行。结果表明，在中高负荷下，PD制动热效率（BTE）高于CTL（最大相差2%）。在10%负荷1400rpm时，DDCL的CO、HC、甲醛排放量分别比PD高88.9%、44.3%和26.5%，DICL的CO、HC、甲醛排放量分别为30.1%、15.3% , 比 PD 低 15.2%。四种燃料之间的差异随着负荷的增加而迅速减小。一氧化氮由于高氮含量 (102.3 μg/g) 和低氢碳 (H/C) 比，PD 的_X排放量最高。十六烷值高的燃油在低负荷时甲醛释放量较少，而H/C较低的燃油在高负荷时甲醛释放量较少。粒径分布在不同载荷下呈双峰形，堆积模式和成核模式的峰值粒径均随着载荷的增加而增大。不同燃料的颗粒排放从高到低的顺序是PD>DDCL>BD58>DICL。此外，多环芳烃 (PAH) 和 PD 的毒性当量 (TE) 的排放量在所有负载下均最高。来自 DDCL、DICL 和 BD58 的可溶性有机组分 (SOF) 的比例高于 PD。